Characterizing smartphone capabilities for seismic and structural monitoring

As seismic events continue to pose significant threats to urban infrastructure, leveraging smartphones equipped with accelerometers for real-time monitoring has gained prominence. To ascertain the reliability and sensitivity of smartphone-based measurements, an in-depth characterization of their response is essential. This article presents a thorough characterization of the performance of typical accelerometers installed on three distinct smartphone models. For this, a novel experimental apparatus has been developed to conduct a comparative study involving three different smartphones against a reference accelerometer. We determine each accelerometer's transfer functions for Fourier frequencies 0.1-40 Hz, evidencing main differences and demonstrating a higher sensitivity than expected. Possible implementation in future distributed networks of heterogeneous and synchronized sensors, capable of independently generating and validating timely alerts in particular seismic events, are also discussed.